Ventilating fan control



Dec. 17, 1940. H. F. MORSE VENTILAIING FAN CONTROL Filed Feb. ,1 19:59

, Irv/ enter" Harold F IVIorse is Attovneg atented Dec. 17,. 1940 y EDSTATES VATENT orrlca VENTILATING'FAN CONTROL 7 Harold F. Morse,Southport, Conn, assignmto General Electric Company, a corporation NewYork Application February 1, 1939, Serial 120.2543

2 Claims. (Cl. 98-116) tion attention is directed to the following de-'scription and the claims appended thereto.

In the accompanying drawing, Fig. 1 is a sectional side elevation of a.ventilating fan embodying my invention; Fig. 2 is a-front view of thefan partly broken away; Fig. 3 is a fragmentary view of the control, andFig. 4 is a perspective view of the switch supporting bracket.

Referring to the drawing, there is shown an electric motor driven fan imounted-in a circular opening or duct 2 in the outside wall 3 of a room.The motor of the fan is shown at la. The lining of the opening comprisesinner and outer tele-,

wall. The inner end section is provided withan inwardly extending flange8a to which are fixed supporting arms 8b fixed to a ring 9a. The ring91; has-flexible arms 91) fixed thereto which resiliently supp rt thefan. Before mounting the fan, the sections 4 and 5 are secured togetherwith the fan and-framemounted thereon, and the assembly is then insertedfrom the outside of the wall 3 to a position in which, ,the frame Irests against the wall surface.

At the upper end of the frame I is mounted a shaft Ill on which a dooror shutter H is hinged. The shutter is biased to the open position shownin dotted lines in Fig. 1 by a coil spring l2 arranged around a rod l3pivoted at M in-ears IS on the telescoping section 5. The upper end of athe coil spring bears against awasher IS on the rod, and the lower endof the-spring bears against a bracket I? through which the rod isslidable. Since the pivot point ll of the rod I3 is at the rear of thepivot III of rthe shutter, the spring always urges the shutter towardthe open position. The movement of the shutter is limited by a washer l8fixed on the rod l3.

The fan is controlled by a switch ls'lmounted on an arm 20 of a bracket2| fixed-to the flange 8a., The switch is connected to the motor bysuitable electrical conductors-not. shown. As shown more clearly in Fig.3, the switch (here 55 shown diagrammatically) has an operating memher22 which is biased by a spring 23 to the circuit closing position. Inother words, when the operating member 22 is released, the switch isclosed by-the biasing spring to start the operation of the fan.

5 The operation of the fan and the opening and 'closing of the shutterare controlled by a flexible pull member 24, such as a bead chain,connected at one end to the switch operating member 22 by means of astrain limiting tension spring 25 and extending therefrom through aguide 28 fixed to the inner telescoping section 4, over a pulley 21carried in a bracket 28 on the inner side of the shutter H, andextending back through the guide 26 and through an opening 29 and akeyhole slot 30 in the bracket 2|. In effect the bead chain is loopedover the pulley, one arm of the loop being connected to the switchoperating member and the other arm of the loop'being extended to aposition accessible to the operator. By pulling on the chain theoperator shortens the loop and swings the shutter to the closedposition. As shown in Fig. 1, the opening 29 may be provided with a,bushing 3|.

To close the shutter and stop the operation of the fan, the bead chainis moved into the enlargedportion of the keyhole slot 30 and is pulleddownward until the shutter reaches the closed position. The bead chainis then moved into the narrow portion of the keyhole slot, which gripsthe bead chain between two of the beads and holds it in this position.Movement of the bead chain to this position closes the shutter and pullsthe switch operating member 22 to the circuit opening position, stoppingthe fan.

To start the operation of the fan, the'bead chain is moved into theenlarged portion of the keyhole slot 30 and released. This releases thetension in the chain and permits movement of the switch operating member22 to the closed position under its biasing spring 23, starting theoperation of the fan. Since the shutter is on an outside wall of thebuilding it may be held in the closed position by ice frozen around itsedges which would prevent its movement to the open position under theaction of the biasing spring l2. The starting of the fan will, however,blow warm air from the room against the shutter, melting the ice. Assoon as the ice is melted the shutter moves to the open position underthe faction of the biasing spring l2.

From the above description it is'apparent that the control of the switchand shutter is dependent I upon the tension in rather than the positionof 5 may be used with varying wall thicknesses withthe bead chain andthat the switch and shutter are capable of'independent operation.

The control has the further advantage that it out adjustment.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. In a room ventilating fan, a duct, a shutter therefor biased to theopen position, a part connected to and movable with the shutter, a fanfor forcing air through the duct against the shutter,

a fan-controlling switch having an operating the force of the shutterbiasing means to a pc. tion corresponding to the closed position'o! theshutter.

2. A room ventilator comprising, a duct ior conducting air through awall, a shutter for closing the duct, means for biasing the shutter toan open position, a fan for blowing air through the duct against theshutter, a fan controlling switch, means biasing the switch to theposition starting the fan, a flexible pull member for controllina' theshutter and switch, and operative connections between the pull memberand the shutter and switchwhereby upon tensioning oi the pull member theswitch is operated to shut oi! the fan and the shutter is closed andupon release of the tension in the pull member the switeh is operated tostart the fan and the shutter is permitted to move to the open positionunder its biasing means.

HAROLD F. MORSE. ,3]

